Szukana fraza: [Abstrakt = "Electroencephalography allows recording the electrical activity of the brain. This method is used for diagnosis purposes as well as in brain–computer interfaces. Focusing on the brain–computer interface, it can be used to let the direct communication between the brain and a computing unit. This device is particularly useful for paralyzed patients or people suffering from a lock–in syndrome. Of the phenomena used in such systems, steady state visually evoked potentials \(SSVEP\) are probably the most common ones. If a subject is asked to focus on the flashing stimulus, a signal of the same frequency may be measured from the subject’s visual cortex. Proper preprocessing steps has to be taken in order to obtain maximally accurate stimuli recognition \(as the specific frequency\). One way to achieve this might be by applying the Blind Source Separation algorithms \(BSS\). BSS are designed to find and remove artifacts from the measured signal, e.g. noises associated with eye blinks or facial muscles contraction. In the present article an utilization of the BSS algorithms in the SSVEP–based EEG study was described. Additionally we report the accuracy of the stimuli categorization as depending on the number of removed components, kind of the blind source separation procedure and the type of the classification algorithm."]

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